36/81 = 4/9
4/9 = 1/9 + 3/9 or 4/9 = 1/9 + 1/3
Now 1/9 + 1/3 = 1/3^m + 1/3^n
so 3^m = 3 hence m = 1 (3^1 = 3)AND
so 3^n = 9 hence n = 2 (3^2 = 9)
therefore m + n = 1+2 = 3
Ans D
exponents
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Plug in m = 1 and solve for n:J N wrote:from veritas prep
if m and n are integers what is m+n?
36/(3^4) = 1/(3^m) + 1/(3^n)
-2
0
2
3
5
36/3� = 1/3¹ + 1/(3^n)
36/81 = 1/3 + 1/(3^n)
4/9 = 1/3 + 1/(3^n)
1/9 = 1/(3^n).
Since 1/9 = 1/3², n = 2.
Thus, m+n = 1+2 = 3.
The correct answer is D.
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My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
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